Move __resolveReference resolvers on to extensions (version-0.x)

gateway-js/src/schema-helper/addResolversToSchema.ts

@@ -19,7 +19,20 @@ export function addResolversToSchema(
 
  if (isAbstractType(type)) {
  for (const [fieldName, fieldConfig] of Object.entries(fieldConfigs)) {
- if (fieldName.startsWith("__")) {
+ if (fieldName === "__resolveReference") {
+ type.extensions = {
+ ...type.extensions,
+ apollo: {
+ // extensions is nullable in graphql@15 so the conditional chain is
+ // necessary for back compat
+ ...type.extensions?.apollo,
+ subgraph: {
+ ...type.extensions?.apollo?.subgraph,
+ resolveReference: fieldConfig,
+ }
+ },
+ };
+ } else if (fieldName.startsWith("__")) {
  (type as any)[fieldName.substring(2)] = fieldConfig;
  }
  }
@@ -65,7 +78,20 @@ export function addResolversToSchema(
  const fieldMap = type.getFields();
 
  for (const [fieldName, fieldConfig] of Object.entries(fieldConfigs)) {
- if (fieldName.startsWith("__")) {
+ if (fieldName === "__resolveReference") {
+ type.extensions = {
+ ...type.extensions,
+ apollo: {
+ // extensions is nullable in graphql@15 so the conditional chain is
+ // necessary for back compat
+ ...type.extensions?.apollo,
+ subgraph: {
+ ...type.extensions?.apollo?.subgraph,
+ resolveReference: fieldConfig,
+ }
+ },
+ };
+ } else if (fieldName.startsWith("__")) {
  (type as any)[fieldName.substring(2)] = fieldConfig;
  continue;
  }

gateway-js/src/typings/graphql.ts

@@ -0,0 +1,31 @@
+import { GraphQLResolveInfo } from 'graphql';
+
+type GraphQLReferenceResolver<TContext> = (
+ reference: object,
+ context: TContext,
+ info: GraphQLResolveInfo,
+) => any;
+
+interface ApolloSubgraphExtensions<TContext> {
+ resolveReference?: GraphQLReferenceResolver<TContext>;
+}
+
+declare module 'graphql/type/definition' {
+ interface GraphQLObjectTypeExtensions<_TSource = any, _TContext = any> {
+ apollo?: {
+ subgraph?: ApolloSubgraphExtensions<_TContext>;
+ }
+ }
+
+ interface GraphQLInterfaceTypeExtensions<_TSource = any, _TContext = any> {
+ apollo?: {
+ subgraph?: ApolloSubgraphExtensions<_TContext>;
+ }
+ }
+
+ interface GraphQLUnionTypeExtensions<_TSource = any, _TContext = any> {
+ apollo?: {
+ subgraph?: ApolloSubgraphExtensions<_TContext>;
+ }
+ }
+}

subgraph-js/src/schema-helper/buildSchemaFromSDL.ts

@@ -107,7 +107,20 @@ export function addResolversToSchema(
 
  if (isAbstractType(type)) {
  for (const [fieldName, fieldConfig] of Object.entries(fieldConfigs)) {
- if (fieldName.startsWith("__")) {
+ if (fieldName === "__resolveReference") {
+ type.extensions = {
+ ...type.extensions,
+ apollo: {
+ // extensions is nullable in graphql@15 so the conditional chain is
+ // necessary for back compat
+ ...type.extensions?.apollo,
+ subgraph: {
+ ...type.extensions?.apollo?.subgraph,
+ resolveReference: fieldConfig,
+ }
+ },
+ };
+ } else if (fieldName.startsWith("__")) {
  (type as any)[fieldName.substring(2)] = fieldConfig;
  }
  }
@@ -153,7 +166,20 @@ export function addResolversToSchema(
  const fieldMap = type.getFields();
 
  for (const [fieldName, fieldConfig] of Object.entries(fieldConfigs)) {
- if (fieldName.startsWith("__")) {
+ if (fieldName === "__resolveReference") {
+ type.extensions = {
+ ...type.extensions,
+ apollo: {
+ // extensions is nullable in graphql@15 so the conditional chain is
+ // necessary for back compat
+ ...type.extensions?.apollo,
+ subgraph: {
+ ...type.extensions?.apollo?.subgraph,
+ resolveReference: fieldConfig,
+ }
+ },
+ };
+ } else if (fieldName.startsWith("__")) {
  (type as any)[fieldName.substring(2)] = fieldConfig;
  continue;
  }

subgraph-js/src/schemaExtensions.ts

@@ -6,12 +6,26 @@ type GraphQLReferenceResolver<TContext> = (
  info: GraphQLResolveInfo,
 ) => any;
 
+interface ApolloSubgraphExtensions<TContext> {
+ resolveReference?: GraphQLReferenceResolver<TContext>;
+}
+
 declare module 'graphql/type/definition' {
- interface GraphQLObjectType {
- resolveReference?: GraphQLReferenceResolver<any>;
+ interface GraphQLObjectTypeExtensions<_TSource = any, _TContext = any> {
+ apollo?: {
+ subgraph?: ApolloSubgraphExtensions<_TContext>;
+ };
+ }
+
+ interface GraphQLInterfaceTypeExtensions<_TSource = any, _TContext = any> {
+ apollo?: {
+ subgraph?: ApolloSubgraphExtensions<_TContext>;
+ };
  }
 
- interface GraphQLObjectTypeConfig<TSource, TContext> {
- resolveReference?: GraphQLReferenceResolver<TContext>;
+ interface GraphQLUnionTypeExtensions<_TSource = any, _TContext = any> {
+ apollo?: {
+ subgraph?: ApolloSubgraphExtensions<_TContext>;
+ };
  }
 }

subgraph-js/src/types.ts

@@ -86,11 +86,11 @@ export const entitiesField: GraphQLFieldConfig<any, any> = {
  }
  }
 
- const resolveReference = type.resolveReference
- ? type.resolveReference
- : function defaultResolveReference() {
-  return reference;
-  };
+ const resolveReference =
+ type.extensions?.apollo?.subgraph?.resolveReference ??
+ function defaultResolveReference() {
+ return reference;
+ };
 
  // FIXME somehow get this to show up special in Studio traces?
  const result = resolveReference(reference, context, info);